how to create snow in cycles?
Perhaps Andrew Price could help you out here. He did a snow scene tutorial, available on his site. It's long, but it's a step-by-step look at how to get soft, slushy and glittery snow using both procedural techniques and texture-based techniques. 

He starts talking about shading around 58:00, but the whole video is worth listening to because he talks about textures, displacements and lighting that can add some much-needed chaos into the scene. 

Suzanne, on the other hand, might need some adjustment from his shader setup. You might need to increase the subsurface scattering (SSS) influence because you're trying to get light through the object, not just glitter on the surface. Just remember that SSS will increase your render times significantly, so use it sparingly.